Under armed guard, the Britons were transported to Mexico City’s International Airport aboard an immigration police bus with bars across the windows. Several pickup trucks full of heavily armed federal police escorted the bus.

The Britons will be barred from re-entering Mexico for two years, said Armando Salinas Torre, Mexico’s assistant Interior Secretary.

The six were trapped inside the cave by floodwaters for more than a week and had refused help from Mexican officials, instead waiting for a British rescue team.

President Vicente Fox then raised questions about the activities of the team, which included British military members. Some members of the Mexican press had speculated the explorers were searching for signs of uranium.

The announcement came hours after the attorney general’s office found there was no evidence the cave explorers did anything illegal in exploring a cave near Mexico City.